全文获取类型
收费全文 | 1134篇 |
免费 | 90篇 |
国内免费 | 97篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 46篇 |
妇产科学 | 8篇 |
基础医学 | 125篇 |
口腔科学 | 37篇 |
临床医学 | 175篇 |
内科学 | 245篇 |
皮肤病学 | 14篇 |
神经病学 | 62篇 |
特种医学 | 123篇 |
外科学 | 98篇 |
综合类 | 59篇 |
一般理论 | 2篇 |
预防医学 | 124篇 |
眼科学 | 24篇 |
药学 | 112篇 |
中国医学 | 3篇 |
肿瘤学 | 49篇 |
出版年
2021年 | 14篇 |
2020年 | 12篇 |
2019年 | 12篇 |
2018年 | 9篇 |
2017年 | 11篇 |
2016年 | 13篇 |
2015年 | 16篇 |
2014年 | 16篇 |
2013年 | 38篇 |
2012年 | 33篇 |
2011年 | 33篇 |
2010年 | 43篇 |
2009年 | 37篇 |
2008年 | 26篇 |
2007年 | 72篇 |
2006年 | 41篇 |
2005年 | 44篇 |
2004年 | 32篇 |
2003年 | 37篇 |
2002年 | 49篇 |
2001年 | 38篇 |
2000年 | 26篇 |
1999年 | 31篇 |
1998年 | 46篇 |
1997年 | 42篇 |
1996年 | 33篇 |
1995年 | 34篇 |
1994年 | 38篇 |
1993年 | 38篇 |
1992年 | 14篇 |
1991年 | 23篇 |
1990年 | 27篇 |
1989年 | 28篇 |
1988年 | 31篇 |
1987年 | 21篇 |
1986年 | 33篇 |
1985年 | 18篇 |
1984年 | 10篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 14篇 |
1979年 | 6篇 |
1978年 | 13篇 |
1977年 | 8篇 |
1972年 | 6篇 |
1971年 | 8篇 |
1970年 | 7篇 |
1930年 | 6篇 |
1929年 | 7篇 |
排序方式: 共有1321条查询结果,搜索用时 15 毫秒
1.
2.
顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究 总被引:5,自引:0,他引:5
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。 相似文献
3.
4.
Secretory antibodies protect mucosal surfaces against transmission of many viruses. Human T-lymphotropic Virus, Type I (HTLV-I) is transmitted via blood products and via sexual contact across mucosal surfaces. We investigated the presence of HTLV-I-specific antibodies in whole saliva samples from 10 seronegative and 28 seropositive volunteers from a hospital in southern Japan. Antibodies directed to HTLV-I antigens were found in the salivas from 22 of 28 (79%) of the seropositive subjects. None of the seronegative individuals showed evidence of salivary antibodies. Antibodies directed to the envelope antigens of the virus were found in 21 of 22 positive saliva samples. Secretory antibodies may be important in preventing mucosal transmission. 相似文献
5.
PC Chamyal A Mehta SL Ojha JR Bhardwaj 《Indian journal of otolaryngology and head and neck surgery》1991,43(1):26-27
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed. 相似文献
6.
7.
8.
J F Walker L M Archibald S R Cherniak V G Fish 《Journal of speech and hearing research》1992,35(1):4-13
The major purposes of this study were to provide normative data on articulation rate in preschool children and to examine the influence on articulation rate of age, gender, context, and utterance length. The subjects were twenty 3-year-old children and twenty 5-year-old children, equally balanced for gender. Durational measures of utterances were analyzed in syllables and phones per second in both spontaneous and imitated speech contexts. The articulation rate of the 5-year-old subjects was significantly faster than that of the 3-year-olds. Spontaneous speech was significantly faster and more variable than imitated speech. Some gender differences were found. Measures in syllables per second and phones per second, although not always yielding identical results, were found to be highly correlated. 相似文献
9.
BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice. 相似文献
10.
A new procedure for calibrating the Video Imaging Technique for Assessing dermal Exposure to pesticides 总被引:1,自引:0,他引:1
B. A. Archibald K. R. Solomon G. R. Stephenson 《Archives of environmental contamination and toxicology》1994,26(3):398-402
Improvements in the calibration techniques used in a Video Imaging Technique for Assessing Exposure (VITAE) were examined. A series of standard curves measuring change in fluorescence with increased tracer deposition within narrow pre-exposure skin tone groupings on volunteer human subjects were developed. Nine highly linear curves were generated. Data from these curves were used to develop calibration curves which permitted the computerized correction of fluorescence based on the pre-exposure skin fluorescence. VITAE estimates of dermal tracer deposition were highly correlated with application rates (r2=0.98). The fluorescent tracer 4-methyl-7-diethylaminocoumarin was found to be stable for up to 48 h in a greenhouse environment when applied to chrysanthemum foliage or alpha-cellulose patches. The percentage of tracer which could be dislodged from chrysanthemum foliage was constant over 48 h. Improvements in the VITAE calibration techniques increase its value in providing full-body dosimetric estimates of dermal exposure to pesticides in enclosed environments. 相似文献